Engines, including compression-ignition engines, spark-ignition engines, gasoline engines, gaseous fuel-powered engines, and other internal combustion engines, may operate more effectively with fuel from which contaminates have been removed prior to the fuel reaching a combustion chamber of the engine. In particular, fuel contaminates, if not removed, may lead to undesirable operation of the engine and/or may increase the wear rate of engine components, such as fuel system components.
Effective removal of contaminates from the fuel system of a compression-ignition engine may be particularly important. In some compression-ignition engines, air is compressed in a combustion chamber, thereby increasing the temperature and pressure of the air, such that when fuel is supplied to the combustion chamber, the fuel and air mixture ignite. If water and/or other contaminates are not removed from the fuel, the contaminates may interfere with and/or damage, for example, fuel injectors, which may have orifices manufactured to exacting tolerances and shapes for improving the efficiency of combustion and/or reducing undesirable exhaust emissions. Moreover, the presence of water in the fuel system may cause considerable engine damage and/or corrosion in the injection system.
Fuel filtration systems serve to remove contaminates from the fuel. For example, some conventional fuel systems may include a fuel filter, which removes water and large particulate matter, and another fuel filter, which removes a significant portion of remaining particulate matter (e.g., smaller contaminates), such as fine particulate matter. However, water may be particularly difficult to separate from fuel under certain circumstances. For example, if water is emulsified in the fuel it may be relatively more difficult to separate from fuel. In addition, for some types of fuel, such as, for example, fuel having a bio-component, it may be relatively more difficult to separate the water from the fuel. Therefore, it may be desirable to provide a filter assembly having an improved ability to separate water from fuel.
An attempt to provide desired filtration is described in U.S. Patent Application Publication No. US 2013/0146524 A1 (“the '524 publication”) to Veit et al., published Jun. 13, 2013. Specifically, the '524 publication discloses a fuel filter having a housing with a fuel inlet, a fuel outlet for cleaned fuel, and a water outlet for water separated from the fuel. A filter element is arranged in the housing and separates the fuel inlet and fuel outlet. The filter element has a filter medium configured as a hollow member for filtering the fuel and a hydrophobic fuel-permeable separating medium embodied as a hollow member for separating water from the fuel. The separating medium is arranged downstream of the filter medium and is positioned inside the filter medium or surrounds the filter medium. Between the filter medium and the separating medium, a precipitation slot is provided having a conical shape and being connected with the water outlet.
Although the fuel filter of the '524 publication purports to separate water from fuel, it may not provide sufficient separation under circumstances where the fuel is emulsified or includes bio-components. Thus, it may not provide a desirable level of fuel filtration.
The flow caps and filter assemblies disclosed herein may be directed to mitigating or overcoming one or more of the possible drawbacks set forth above.